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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Estudo e desenvolvimento de sistema baseado em sensores de pressão aplicados à ortodontia

Crivellaro, Fernando Sacilotto January 2016 (has links)
Este trabalho tem por objetivo o estudo e o desenvolvimento de uma solução de engenharia para o mapeamento e caracterização da oclusão dentária, não somente no âmbito de sua distribuição ao longo da arcada, mas também através da mensuração da intensidade de pressão nos pontos de contato oclusal interarco. Neste sentido, empregaram-se esforços no aprofundamento do conhecimento neste campo da Odontologia, assim como, na elaboração de um sistema experimental que, utilizando sensores de pressão/força resistivos (FSR) específicos para uso odontológico, viabilizou a análise do estado da oclusão, atuando como agente facilitador no diagnóstico de desequilíbrios oclusais. Inicialmente, são apresentados e esclarecidos os principais conceitos da esfera odontológica, os quais são tomados como base para todos os projetos deste trabalho, além da abordagem referente às formas de contato entre os dentes, aos diferentes tipos de oclusão e seus problemas. Em relação ao desenvolvimento do sistema, foram projetadas duas placas de circuito impresso para interface com os sensores e elaborados o firmware de acesso ao hardware, assim como o software de gerenciamento global do sistema. Todos os blocos do circuito de condicionamento foram avaliados e as suas funcionalidades validadas. Do mesmo modo, a caracterização da resposta dos sensores e a sua homogeneidade ao longo da extensão sensível foram analisadas, demonstrando que a resistência elétrica varia de forma análoga em todas as áreas do sensor. Através de ensaios realizados com sujeito envolvido no projeto, estabeleceu-se um comparativo entre a utilização do papel carbono e o sistema desenvolvido, mostrando as vantagens na utilização do segundo, principalmente atreladas à capacidade de avaliação da intensidade dos contatos oclusais. Por fim, ainda se valendo do uso paralelo do papel carbono, foram efetuados ensaios de análise da oclusão em sujeito envolvido no projeto utilizando placa miorrelaxante, possibilitando a utilização da capacidade do sistema desenvolvido para executar ajustes precisos na placa, com a finalidade de manter o balanço de pressões oclusais entre ambos os lados da arcada. / This essay has as objective the study and development of an engineer solution for the dental occlusion mapping and characterization, not only related to the interarch occlusal contact distribution, but also through the pressure magnitude measuring in each. In this sense, was employed effort in the Odontological knowledge increasing and also in the system elaboration allowing the occlusion state evaluation and acting as an easier agent in the occlusion disturbs diagnosing using a specific pressure/force sensing resistor (FSR) for dental use. Initially the main concepts of the Odontological sphere are presented, clarified and took as a base for all the projects in this essay. Besides this, different teeth contacts shapes are shown, as well as the occlusion’s types and its problems. In the system development, two printed circuit boards were designed for sensor interfacing. The hardware access through the firmware was elaborated, even as the global system managing software. All the conditioning circuit blocks and functionalities were evaluated and validated. In the same way, the sensor’s output and its homogeneity through all the sensible extension were evaluated, showing that the sensor’s electric resistance changes in the same form in all the sensor’s areas. In addition, it was showed the advantages of the developed system over the articulation paper through trials with a subject that is part of the project, showing the capacity of the system in the occlusion contacts magnitude evaluation. Ultimately, also in an articulation paper versus the developed system comparison, it was made occlusion analysis trials with subject using a night guard for teeth grinding (bruxism), showing the system capacity of precisely adjust the night guards for pressure balance between the both arch sides.
12

Lean Into Your Ride : Intuitive Handsfree Control for an Electric Skateboard

Grape, Elias January 2020 (has links)
Skateboards have been around since at least the 1950’s, and skateboarding is most commonly knownas an extreme sport. However, skateboards can be very useful when commuting as they have continued to evolve since the 1950’s, not quite in to the hover board that Marty McFly rides on in Back to the Future, but in to skateboards equipped with electric motors that propels them forward. Electric skateboards, as they are called, are one of the vehicle types that are changing the way humans move around cities. Vehicles that are needed in order to fulfill present and future commuting needs. However, electric skateboards have not yet reached their full potential, especially regarding how their speed is controlled. Current speed control systems gives a riding experience that feels unnatural compared to riding a regular skateboard, and improving upon them can potentially make electric skateboards even safer to ride. In this thesis, an active style of riding, like skateboarding, is compared to the reactive style of riding that is provided by the speed control systems existent in electric skateboards today. The thesis presents a speed control system that utilizes an active style of riding, and the concept is tested by the development of a pedobarography system that can read the interaction between the riders feet and the skateboard deck.
13

Impact of Mobility Models on Routing Protocols for Various Traffic Classes in Mobile Ad Hoc Networks

Alash, Hayder Majid Abdulhameed 02 May 2016 (has links)
No description available.
14

Precision measurement of the e+e− → π + π−(γ ) cross-section with ISR method

Wang, L.-L. 26 May 2009 (has links) (PDF)
Vacuum polarization integral involves the vector spectral functions which can be experimentally determined. As the dominant uncertainty source to the integral, the precision measurement of the %born cross section of $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ as a function of energy from $2\pi$ threshold to 3GeV is performed by taking the ratio of $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ cross section to $e^+e^-\rightarrow\mu^+\mu^-(\gamma)$ cross section which are both measured with {\babar\ }data using ISR method in one analysis. Besides that taking the ratio of the cross sections of the two processes can cancel several systematic uncertainties, the acceptance differences between data and MC are measured using the same data, and the corresponding corrections are applied on the efficiencies predicted by MC which can control the uncertainties. The achieved final uncertainty of the born cross section of $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ in $\rho$ mass region ($0.6\sim0.9$GeV) is 0.54\%. As a consequence of the new vacuum polarization calculation using the new precision result of the $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ cross section, the impact on the SM prediction of muon anomalous magnetic moment $g-2$ is presented, which is also compared with other data based predictions and direct measurement.
15

Crowd Detection During IndoorEvents Using FSR Sensor WithMicrocontrollers : Crowd detection and monitoring

Hama, Mohamad January 2024 (has links)
Overcrowding during indoor events can be risky, in-case of any kind of a hazard such as fire.This solution address this by providing real-time crowd detection solution using Force-SensingResistor (FSR) sensors, referred sensor (IR) and microcontrollers. The solution needs to offer accurate data in real-time to the event managers including number of people and entrancerate to help when and if the event areas will be overcrowded, thereby enhancing event safetyand decision-making. This thesis indicate that the system offers essential real-time data forevent safety with an accuracy of 87.25%. These data will assists event managers in makinginformed decisions to avoid the risks of overcrowding. This thesis evaluates the effectivenessof our system in comparison to other systems, discussing what we’ve learned, suggest possibleimprovements, and talk about whether our system could be useful in real-world indoor events.
16

Mesure de la section efficace différentielle de production du boson Z se désintégrant en paires électron-position, dans l'expérience ATLAS

Doan, Thi Kieu Oanh 28 November 2012 (has links) (PDF)
La première mesure du spectre en phi*_eta du boson Z à 7 TeV a été réalisée dans cette thèse. Cette variable permet de sonder la dynamique de production des Z de façon fine. L'échantillon complet des données enregistrées par ATLAS en 2011 a été utilisé ce qui correspond à 4.7/fb de luminosité intégrée. Les résultats de cette mesure sont publiés dans la Ref. [18] fondé sur la note interne Ref. [69]. La section efficace différentielle de Z->ee en fonction phi*_eta a été mesurée et comparée aux calculs perturbatifs à ordre fixé, avec/sans resommation pour la région des petits phi*_eta. Le code RESBOS fournit la meilleure description des données, cependant il est incapable de reproduire, à mieux de 4%, la forme détaillée de la section efficace mesurée. La section efficace différentielle a également été comparée aux prédictions de différents générateurs Monte Carlo interfacés avec un algorithme de parton shower. Les meilleures descriptions du spectre en phi*_eta mesuré sont données par les générateurs SHERPA et POWHEG+PYTHIA8. La mesure précise de la section efficace différentielle en phi*_eta fournit des informations précieuses pour l'ajustement des codes Monte Carlo. La précision expérimentale typique de cette mesure (~0.5%) est dix fois meilleure que la précision des calculs théoriques et elle est donc aussi précieuse pour contraindre la théorie. La mesure du spectre en ptZ a également été faite pour quantifier l'incertitude systématique de cette mesure en utilisant la grande statistique de l'échantillon de données. Cela permet de comparer deux mesures qui traitent de l'impulsion transverse du boson Z. Dans la plupart du domaine en phi*_eta l'incertitude systématique de la mesure de ptZ est deux fois plus grande que celle de la mesure de phi*_eta. Cette comparaison confirme l'intérêt de la variable phi*_eta. Les résultats présentés dans cette thèse ont beaucoup d'implications pour les études futures. Ajustant les générateurs Monte Carlo en utilisant les résultats de la mesure précise du spectre en phi*_eta minimisera l'incertitude sur leurs paramètres. Une mesure de la section efficace doublement différentielle en ptZ et phi*_eta est intéressante pour mieux comprendre la corrélation entre ces deux variables. La mesure précise du spectre en ptZ utilisant la variable phi*_eta peut être appliquée au spectre en ptW et on sait que des mesures plus fines du ptW sont importante pour une détermination précise de la masse du boson W. De plus, une compréhension précise du spectre en ptZ est importante pour comprendre les propriétés cinématiques de la production du boson de Higgs.
17

Numerical modeling of flame spread over spherical solid fuel under low speed flow in microgravity:Model development and comparison to space flight experiments

Endo, Makoto 31 May 2016 (has links)
No description available.
18

Mesure de la section efficace différentielle de production du boson Z se désintégrant en paires électron-position, dans l'expérience ATLAS / Measurement of the differential cross section of the production Z boson decaying into electron-positron pairs in the ATLAS experiment

Doan, Thi Kieu Oanh 28 November 2012 (has links)
La première mesure du spectre en phi*_eta du boson Z à 7 TeV a été réalisée dans cette thèse. Cette variable permet de sonder la dynamique de production des Z de façon fine. L’échantillon complet des données enregistrées par ATLAS en 2011 a été utilisé ce qui correspond à 4.7/fb de luminosité intégrée. Les résultats de cette mesure sont publiés dans la Ref. [18] fondé sur la note interne Ref. [69]. La section efficace différentielle de Z->ee en fonction phi*_eta a été mesurée et comparée aux calculs perturbatifs à ordre fixé, avec/sans resommation pour la région des petits phi*_eta. Le code RESBOS fournit la meilleure description des données, cependant il est incapable de reproduire, à mieux de 4%, la forme détaillée de la section efficace mesurée. La section efficace différentielle a également été comparée aux prédictions de différents générateurs Monte Carlo interfacés avec un algorithme de parton shower. Les meilleures descriptions du spectre en phi*_eta mesuré sont données par les générateurs SHERPA et POWHEG+PYTHIA8. La mesure précise de la section efficace différentielle en phi*_eta fournit des informations précieuses pour l’ajustement des codes Monte Carlo. La précision expérimentale typique de cette mesure (~0.5%) est dix fois meilleure que la précision des calculs théoriques et elle est donc aussi précieuse pour contraindre la théorie. La mesure du spectre en ptZ a également été faite pour quantifier l’incertitude systématique de cette mesure en utilisant la grande statistique de l’échantillon de données. Cela permet de comparer deux mesures qui traitent de l’impulsion transverse du boson Z. Dans la plupart du domaine en phi*_eta l’incertitude systématique de la mesure de ptZ est deux fois plus grande que celle de la mesure de phi*_eta. Cette comparaison confirme l’intérêt de la variable phi*_eta. Les résultats présentés dans cette thèse ont beaucoup d’implications pour les études futures. Ajustant les générateurs Monte Carlo en utilisant les résultats de la mesure précise du spectre en phi*_eta minimisera l’incertitude sur leurs paramètres. Une mesure de la section efficace doublement différentielle en ptZ et phi*_eta est intéressante pour mieux comprendre la corrélation entre ces deux variables. La mesure précise du spectre en ptZ utilisant la variable phi*_eta peut être appliquée au spectre en ptW et on sait que des mesures plus fines du ptW sont importante pour une détermination précise de la masse du boson W. De plus, une compréhension précise du spectre en ptZ est importante pour comprendre les propriétés cinématiques de la production du boson de Higgs. / The first measurement of the phi*_eta spectrum of Z bosons at 7 TeV of pp collisions has been studied in this thesis, which is an alternative way to probe the transverse momentum of Z bosons. The full data sample recorded by the ATLAS detector during 2011 run of the LHC was used, which corresponds with 4.7/fb integrated luminosity. The results of this measurement were reported in Ref. [18] supported by the internal note in Ref. [69]. The differential cross section of Z->ee as a function of phi*_eta has been measured and compared to fixed order perturbative QCD calculations with/without a resummation for the low phi*_eta region. Calculations using RESBOS provide the best descriptions of the data. However, they are unable to reproduce the detailed shape of the measured cross section to better than 4%. The differential cross section was also compared to predictions from different Monte Carlo generators interfaced to a parton shower algorithm. The best descriptions of the measured phi*_eta spectrum are provided by SHERPA and POWHEG+PYTHIA8 Monte Carlo event generators. The precise measurement of the differential cross section as a function of phi*_eta provides valuable information for the tuning of MC generators. The typical experimental precision of this measurement (~0.5%) is ten times better than the typical theoretical precision and therefore is valuable to constrain the theoretical predictions further. The ptZ measurement has been also studied to quantify the systematic uncertainty of this measurement using the high statistic data sample. This allows to compare two measurements which both address the physics issues of the Z transverse momentum. In most of the phi*_eta range, the systematic uncertainty of the ptZ measurement is two times larger than the one of the phi*_eta measurement. This comparison confirms the interest for the phi*_eta variable. The measurements presented in this thesis has many implications for future studies. Tuning MC generators using the result of the precise measurement of the phi*_eta spectrum will minimize the uncertainty on the tuned parameters. A double differential cross section measurement as a function of ptZ and phi*_eta is interesting to understand the correlation between ptZ and phi*_eta variables. The precise measurement of the ptZ spectrum using the new variable phi*_eta can be applied to ptZ. More precise measurement of ptZ are important to obtain precise measurements of the W mass. In addition, a precise understanding of the ptZ spectrum is important to understand kinematic properties of Higgs boson production.

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